Car owners with the central Brighton BN1 postcode are paying some of the highest insurance premiums in the South.

An AA study has shown the cost of insuring a car in BN1, which includes the town centre and areas directly north, has increased by a fifth in the past year.

Insurance companies use postcodes to work out premiums for cars and houses.

Assessment is based on the number of reported car thefts within the postcode district, the likelihood of break-ins and the social economic profile.

AA Insurance Services used the profile of a 37-year-old factory worker with a 35-year-old partner, a clean licence and a no claims discount wanting comprehensive cover on a mid-range Ford Escort.

Using crime and social economic data for the BN1 postcode area, it came up with a £286 cost for BN1 - a 21 per cent rise on last year.

In the South excluding London, only LU2 in Bedforshire, on the outskirts of Luton, is more expensive.

Parts of London, notably Paddington and the heart of the East End in Bethnal Green, attract higher premiums.

The increase in insurance costs in BN1 has been influenced by a spate of car thefts last year in central Brighton in which some vehicles were torched and abandoned on the Downs.

Police in Brighton have launched a special operation to deal with the increase in car crime.

The AA survey covered nearly 80 postcodes around the UK. The cheapest area, at £229, was Llandudno in north Wales.